One-letter domains: the rarest names online
Why only three one-letter .com domains exist (X.com, Z.com and Q.com), the stories behind them, and where you can still get single-letter names.
One-letter domains are the rarest names on the internet. There are only 26 letters, and in .com, almost all of them were locked away decades ago. That rarity is exactly what makes them legendary.
Only three one-letter .com domains exist
In the early 1990s, only a handful of single-letter .com names had been registered. Internet pioneer Jon Postel then reserved the remaining letters so no one could claim them. Today just three one-letter .com names are in use:
| Domain | The story |
|---|---|
| X.com | Elon Musk's online bank in 1999, which merged into what became PayPal. Musk bought the domain back from PayPal in 2017. After he bought Twitter, it rebranded as X in July 2023 and moved fully to x.com in May 2024. Read the full story. |
| Z.com | Used by Nissan for its Z sports cars. Japanese internet company GMO Internet bought it from Nissan for about $6.8 million (800 million yen), announced in 2014. |
| Q.com | Has long belonged to a telecom company. It has never come up for public sale. |
The other 23 letters in .com are reserved and can't be registered by anyone. ICANN has discussed releasing them at auction over the years, but they remain locked.
One-letter names in other endings
Many country and newer endings do allow single-letter names, usually sold as premium names or through registry auctions at high prices. For example, Overstock reportedly paid $350,000 for o.co in 2011 when .co launched, and you'll see short links like n.pr (NPR) built on single letters in country endings.
Why they're so valuable
- Absolute scarcity: there are only 26 per ending, and fewer in practice.
- Perfect for brands: instantly memorable, impossible to misspell.
- Prestige: owning one signals size and seriousness.
Can you buy one?
Realistically, not in .com. In other endings, check the registry's premium list or registrar search, and expect premium prices and sometimes premium renewals. Single characters with numbers (like 1 or 7) follow similar rules in most endings.
For more realistic short names, see two-letter and three-letter domains.
Sources
- Snagged: The history of single-letter domains
- Quartz: Elon Musk buys back X.com from PayPal (2017)
- Domain Name Wire: Nissan sells Z.com to GMO for $6.8 million
Questions
How many one-letter .com domains are there?
Only three are in use: X.com, Z.com and Q.com. The other 23 letters were reserved in the early 1990s and can't be registered.
Who owns X.com?
Elon Musk. He used it for his 1999 online bank, bought it back from PayPal in 2017, and it now hosts X, formerly Twitter.
Can I register a one-letter domain?
Not in .com. Some country and newer endings offer single-letter names as premium registrations or at auction.